Possible mouse/ATA problems in -STABLE

[Soren Schmidt]

It seems Murray Stokely wrote:
> > I think that maybe the new ATA drivers are staying in the interrupt a
> > bit longer and causing data to be dropped.
> > 
> > I have reverted to 1-sep -STABLE and it seems stable (so far), I am
> > going to try a new -STABLE and look at the interrupt counts.
> > 
> > The -STABLE ATA drivers were MFC'd - after this merge I see the
> > following comment for a commit on ata-dma.c (revision 1.122)
> > 
> > ...
> > "This pushed the time spent between starting the ATA command and
> > starting the DMA engine over the hill for some controllers
> > (especially the Silicon Image DS3112a) and caused what looked
> > like lost interrupts."
> > 
> > - so possibly we need another MFC... ?
> 
> I think maybe we do.  Unfortunately Soeren is not working on ATA in
> -stable.  Is there anyone else (a committer?) who can verify that this
> analysis is correct?  Can we circulate a patch?

That change in -current doesn't not easily apply to -stable, and does
not change the amount of time spent in interrupt at all. The change
in current fixes total lockups of some controllers when the time
busdma use to setup the SG list is too long.

-Søren